Llechryd Trunk Main
Client: Dwr Cymru Welsh Water
Scheme: 300mm ductile iron main from Llechryd WTW
This contract involved laying a 300mm ductile iron main from Llechryd Water Treatment Works to a Mynydd Grogwy service reservoir near Rhos Hill, Cardigan. The length of the water main was 7,100 metres. The water main crossed watercourses including the Teifi river near Llechryd Water Treatment works.
To meet the Ecological requirement the river crossings needed to be installed using trenchless technology. To carry out the Teifi river crossing cofferdams were installed 9 metres deep either side of the water course. Micro tunnelling methods were then used to install twin 600mm under the Teifi river, the shots were approximately 60 metres long. The ground encountered was rock, river gravels and clay. The 300mm ductile iron pipe were then pulled through the sleeve pipes and using temporary works the pipework was brought to the required invert levels of the valve complexes.
YBCE used their directional drilling equipment to install the 300mm ductile iron pipework under the Morgenau river at Pontrhydyciert.
The project was successfully completed and the new water main pressured tested and chlorinated. The working pressure of the new water main is 26 bar.
The work was carried out over a 64 week programme.
This example demonstrates YBCE capability of undertaking deep and nominal depth pipelaying work.
